Carbapenem antibiotics are a type of β-lactam antibiotics initially developed in 1970s. Carbapenems attracted a lot of attention for the broad antibacterial spectrum, potent antibacterial activity and stability towards β-lactamase. The structural features of carbapenems include: (1) the sulfur atom at 1-position of the parent core of penam is replaced by a carbon atom, a feature that activates the β-lactam antibiotics by ring strain introduced by the fused five-membered ring; (2) a double bond is introduced at 2-position, which activates the antibiotics by the delocalization of the β-lactam nitrogen lone pair into a conjugated double bond system; and (3) a hydroxyethyl group side chain at 6-position is trans-configuration.
There are a number of carbapenem type of antibiotics available on the market, such as imipenem, meropenem, ertapenem, doripenem, panipenem, and bioapenem. Those carbapenem antibiotics have certain clinical shortcomings including relatively short half life and intravenous administration. Furthermore, the microbes have grown to be more drug resistance due to the overuse of antibiotics. Thus, there is a strong need to develop novel carbapenem antibiotics.